Electric switch casing



Oct. 16, 1951 F. P. GATES 2,571,859

ELECTRIC SWITCH CASING Originai Filed April 29, 1944 i v a I I LL . i i I 4 INVENTOR FREDERIC P. GATES Patented Oct. 16, 1951 ELECTRIC SWITCH CASING Frederic P. Gates, Toronto, Ontario, Canada, as-

signor to The Arrow-Hart & Hegman Electric 00., Hartford, Conn., a corporation of Connecticut Original application April 29, 1944, Serial No. 533,355. Divided and this application April 1,

1948, Serial No. 18,428.

In Canada May 29,

4 Claims. (Cl. 17453) This invention relates to electric switch casings, particularly for switches wherein examina tion and inspection of contacts, their clearance, and other interior mechanism is not possible after the contacts and mechanism are assembled in the casing. A switch of the sort to which I refer is described and illustrated in my copending application Serial No. 533,355, filed April 29, 1944, entitled Electric Range Switch, patented November 23, 1948, No. 2,454,646, of which the present application is a division.

Thus, an object of the invention is to provide for inspection of the interior contacts and parts after they are assembled in a switch casing, by provision of removable casing walls. A related object is to provide cooperating base structure and flexible walls shaped so that the Walls may be quickly and easily snapped into place, and may be readily removed.

Other objects and advantages will appear as the invention is described in connection with the accompanying drawing.

In the drawings Fig. 1 is a plan view of a switch casing embodying the invention;

Fig. 2 is a side view of the switch casing Fig. 3 is an end View of the switch casing partly broken away.

Referring to the drawings the casing comprises an insulation base 8| of rectangular plan, hollowed out in its central portion for the reception of the switch operating parts and contacts. The casing illustrated is particularly adapted for use with a switch mechanism and contacts as illustrated and described in my above identified copendingapplication because in that form, as in certain other switches it is impossible otherwise to inspect the contacts after assembly. However the invention is not limited to use with that particular switch and contact structure.

In switches of the type disclosed in said copending application, it is particularly necessary to be able to inspect the action, alignment and engagement of the contacts before the switch is passed on for use and sale. To enable this to be done, removable side walls 88 may be provided, which may be snapped into place after the inspection. Referring to Figs. 1, 2 and 3, the casing or base 8! there shown has its side walls open with a semi-circular upward extension 82 from the bottom edge of the opening 83 to provide additional rigidity to the casing. In the bottom edges of the opening are grooves 84 to receive the feet 86 of a thin wall plate of sheet insulation 80 whose outline is substantially the same as that of the opening 83. To hold the top edge of the wall plate 80, the side edges of a metal switch cover plate 85 may be bent over to provide flanges 88 divided at their center by tongue 98 bent parallel to the flanges but spaced therefrom a distance slightly greater than, but approximating the thickness of the wall plate 80. Because of slight resiliency of the wall plate, it is possible, after inserting feet 86 in grooves 84, to snap the upper edge between the flange 88 and the tongue 90, or vice versa.

Alternatively, grooves may be formed in the short side edges of the opening 83 and the plate flexed to enable insertion of the short edges of the plate therein. In such case, the flanges 88 and tongues 98 and grooves 84 may be omitted, and the top and bottom edges of the plate 80 will abut the under side of the cover and the bottom edge of the opening 83, respectively.

The cover plate may be held in place by bolts or secured by arms 92 of the shape shown in Fig. 3, extending from the ends of the cover and bent down into channels in the casing walls.

Many modifications within the scope of my invention will be apparent to those skilled in the art. Therefore I do not limit it to the speecific embodiment shown.

I claim:

1. A casing for an electric switch of the class wherein a switch operating spindle carries a contact operating member which conceals and prevents access to contacts beneath said member after the switch is assembled in the casing but wherein inspection and adjustment of the contacts are necessary after such assembling, said casing comprising a hollow insulating base having side walls, a bottom wall and an open top, a recess in a side wall of size and dimension to permit inspection and adjustment of the switch contacts, a cover member extending over said base and secured thereon over the assembled switch in the base, flanges on the side edge of said cover member, a tongue on said edge offset from but substantially parallel to said flanges, a flexible insulating plate having portions engageable in slots in said base and being also engageable with said flanges and tongue, said plate being flexible to enable its engagement with said cover member and base and to close said recess in the side wall of the base after said cover is secured on said base.

2. A casing for an electric switch of the class wherein a switch operating spindle carries a contact operating member which conceals and prevents access to contacts beneath said member after the switch is assembled in the casing but wherein inspection and adjustment of the contacts are necessary after such assembling, said casing comprising a hollow insulating base having a side wall recessed from its top edge to a depth and width to permit inspection and adjustment of the switch contacts, a cover member extending over said base and secured thereon over the assembled switch in the base, a flexible side wall plate of insulating material having substantially straight side and top edges closing said recess and having its top edge engaged by said cover member, said base being grooved in the periphery of said recess and receiving said plate, the interengagement of the edges of the plate with the side edges of the base recess upon flexing of the plate after the base and cover member are secured together thus holding the plate in place.

3. A casing for an electric switch of the class wherein a switch operating spindle carries. contact operating member which conceals and prevents access to contacts beneath said member after the switch is assembled in the casing but wherein inspection and adjustment of the contacts are necessary after such assembling, said casing comprising a hollow insulating base having a side wall recessed from its top edge to a depth and width to permit inspection and adjustment of the switch contacts, means formed into the lower edge of said recess to receive the edge of a plate, a cover member extending over said base and secured thereon over the assembled switch in the base, a flexible insulating plate engaged and held by said cover member and said means formed in the lower recess edge, said plate being flexible so as to be flexed into engagement,

FREDERIC P. GATES.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 646,222 Keil et a1. Mar. 2'7, 1900 829,909 Craft Aug. 28, 1906 1,257,730 Moulthrop Feb. 26, 1918 1,462,209 Miner July 17, 1923 2,028,375 Andre Jan. 21, 1936 2,357,162 Barbour 1 Aug. 29, 1944 

